Per-Olov Löwdin Explained

Per-Olov Löwdin
Birth Date:	October 28, 1916
Birth Place:	Uppsala, Sweden
Death Place:	Uppsala, Sweden
Nationality:	Swedish
Field:	Quantum chemistry
Work Institution:	University of Uppsala University of Florida
Alma Mater:	Uppsala University
Doctoral Advisor:	Ivar Waller
Known For:	Löwdin perturbation theory Löwdin rules Löwdin weights Natural bond orbital Orthogonalization Proton tunneling Quantum biology
Prizes:	Niels Bohr Medal (1987) Lavoisier Medal (1975) St. Olav's Medal (1975) Björkénska priset (1973)

Per-Olov Löwdin (October 28, 1916 – October 6, 2000) was a Swedish physicist, professor at the University of Uppsala from 1960 to 1983, and in parallel at the University of Florida until 1993.

A former graduate student under Ivar Waller, Löwdin formulated in 1950 the symmetric orthogonalization scheme for atomic and molecular orbital calculations, greatly simplifying the tight-binding method.^{[1] [2]} This scheme is the basis of the zero-differential overlap (ZDO) approximation used in semiempirical theories. In 1956 he introduced the canonical orthogonalization scheme, which is optimal for eliminating approximate linear dependencies of a basis set.^[3] These orthogonalization procedures are widely used today in all modern quantum chemistry calculations.^{[4] [5]}

The famous 'Löwdin's pairing theorem' used in restricted open-shell Hartree–Fock (ROHF), unrestricted Hartree–Fock (UHF) and generalized valence bond (RES-GVB) theories is not his. According to himself, George G. Hall and King made the formal proposition after an informal suggestion by Löwdin.

His Löwdin partitioning technique for quantum chemistry problems is best appreciated through the series of 14 papers on perturbation theory published between 1963 and 1971.

He was also a very active teacher, starting the Summer Schools of Quantum Chemistry at Uppsala around 1958. In 1959 and 1960, Löwdin started the Quantum Theory Project at the University of Florida as a sister project to the Uppsala Quantum Chemistry Group. In 1964 he was joined by John C. Slater from MIT. The International Winter Institutes (held initially at Sanibel Island, and later at Gainesville) provided the initiation of hundreds of Latin American young scientists during the eighties and nineties. In 1960 he founded the Sanibel Symposium in conjunction with the Winter Institute. They have been held every year since 1960.

Löwdin was elected a member of the Royal Swedish Academy of Sciences in 1969, the American Philosophical Society in 1983,^[6] and was a member of the committee for the Nobel Prize in Physics from 1972 to 1984. He was the founder of the International Journal of Quantum Chemistry and of the series Advances in Quantum Chemistry. He was a foundation member of the International Academy of Quantum Molecular Science.

Publications

• Elementa. Lorentz-Transformationen och den Kinematiska Relativitetsprincipen. 22. 10. 161–169. 1939. Löwdin. Per-Olov.
• Arkiv för Matematik, Astronomi och Fysik. A quantum mechanical calculation of the cohesive energy, the interionic distance, and the elastic constants of some crystals. 35A. 1–10. 1947.
• Arkiv för Matematik, Astronomi och Fysik. A quantum mechanical calculation of the cohesive energy, the interionic distance, and the elastic constants of some ionic crystals. II. The elastic constants c12 and c44. 30. 1–18. 1948.
• Per-Olov. Löwdin. The Journal of Chemical Physics. On the non-orthogonality problem connected with the use of atomic wave functions in the theory of molecules and crystals. 10.1063/1.1747632. 1950. 18. 365. 1950JChPh..18..365L. 3 .
• Arkiv för Fysik. On the calculation of certain integrals occurring in the theory of molecules, especially three-center and four-center integrals. 3. 147–154. 1951.
• Arkiv för Fysik. A note on the numerical calculation of asymptotic phases with a numeric study of Hulthen's variational principle. 3. 155–166. 1951.
• Per-Olov. Löwdin. The Journal of Chemical Physics. Calculation of Electric Dipole Moments of some Heterocyclics. 10.1063/1.1748043. 19. 10. 1323. 1951. 1951JChPh..19.1323L .
• Per-Olov. Löwdin. The Journal of Chemical Physics. A note on the quantum-mechanical perturbation theory. 10.1063/1.1748067. 19. 11. 1396. 1951. 1951JChPh..19.1396L .
• Per-Olov. Löwdin. The Journal of Chemical Physics. On the quantum-mechanical calculation of the cohesive energy of molecules and crystals. Part I. A general energy formula for the ground state. 10.1063/1.1748125. 19. 12. 1570. 1951. 1951JChPh..19.1570L .
• Per-Olov. Löwdin. The Journal of Chemical Physics. On the quantum-mechanical calculation of the cohesive energy of molecules and crystals. Part II. Treatment of the alkali metals with numerical applications to sodium. 10.1063/1.1748126. 19. 12. 1579. 1951. 1951JChPh..19.1579L .
• Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.90.120. Studies of atomic self-consistent Fields. I. Calculation of Slater functions. 90. 1. 120–125. 1953. 1953PhRv...90..120L .
• Per-Olov. Löwdin. The Journal of Chemical Physics. Approximate formulas for many-center integrals in the theory of molecules and crystals. 10.1063/1.1698901. 21. 2. 374. 1953. 1953JChPh..21..374L .
• Per-Olov. Löwdin. The Journal of Chemical Physics. On the molecular-orbital theory of conjugated organic compounds with application to the perturbed benzene ring. 10.1063/1.1698934. 21. 3. 496–515. 1953. 1953JChPh..21..496L . 53968623.
• Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.94.1600. Studies of atomic self-consistent fields. II. Interpolation problems. 94. 6. 1600–1609. 1954. 1954PhRv...94.1600L .
• Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.97.1474. Quantum theory of many-particle systems. I. Physical interpretations by means of density matrices, natural spin-orbitals, and convergence problems in the method of configurational interaction. 97. 6. 1474–1489. 1955. 1955PhRv...97.1474L .
• Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.97.1490. Quantum theory of many-particle systems. II. Study of ordinary Hartree-Fock approximation. 97. 6. 1490–1508. 1955. 1955PhRv...97.1490L .
• Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.97.1509. Quantum theory of many-particle systems. III. Extension of the Hartree-Fock scheme to include degenerate systems and correlation effects. 97. 6. 1509–1520. 1955. 1955PhRv...97.1509L .
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560550203. The historical development of the electron correlation problem. 55. 2. 77–102. 1955.
• Harrison. Shull. Per-Olov. Löwdin. The Journal of Chemical Physics. Natural spin orbitals for helium. 10.1063/1.1742383. 23. 8. 1565. 1955. 1955JChPh..23.1565S .
• Per-Olov. Löwdin. Advances in Physics. 10.1080/00018735600101155. Quantum theory of cohesive properties of solids. 5. 17. 1. 1956. 1956AdPhy...5....1L .
• Harrison. Shull. Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.101.1730. Natural orbitals in the quantum theory of two-electron systems. 101. 6. 1730–1739. 1956. 1956PhRv..101.1730L .
• Per-Olov. Löwdin. Klaus. Appel. Physical Review. 10.1103/PhysRev.103.1746. Studies of atomic self-consistent fields. Analytics wave functions for the argon-like ions and for the first row of the transition metals. 103. 6. 1746–1755. 1956. 1956PhRv..103.1746L .
• Harrison. Shull. Per-Olov. Löwdin. The Journal of Chemical Physics. Correlation splitting in helium-like ions. 10.1063/1.1743093. 25. 5. 1035. 1956. 1956JChPh..25.1035S .
• Per-Olov. Löwdin. The Journal of Physical Chemistry. Present situation in Quantum Chemistry. 61. 1. 10.1021/j150547a012. 55–68. 1957.
• Per-Olov. Löwdin. Spin Degeneracy Problem. Colloq. Intern. Centre Natl. Recherche Sci. (Paris). 82. 23. 1958.
• Harrison. Shull. Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.110.1466. Variation theorem for excited states. 110. 6. 1466–1467. 1958. 1958PhRv..110.1466S .
• Lajos. Rèdei. Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.114.752. Combined use of the methods of superposition of configurations and correlation factor on the ground states of helium-like ions. 114. 3. 752–757. 1959. 1959PhRv..114..752L .
• Per-Olov. Löwdin. Journal of Molecular Spectroscopy. 10.1016/0022-2852(59)90006-2. Scaling problem, virial theorem, and connected relations in quantum mechanics. 3. 1–6. 46–66. 1959. 1959JMoSp...3...46L .
• Harrison. Shull. Per-Olov. Löwdin. The Journal of Chemical Physics. Superposition of configurations and natural spin orbitals. Applications to the He problem. 10.1063/1.1730019. 30. 3. 617. 1959. 1959JChPh..30..617S .
• Per-Olov. Löwdin. 10.1146/annurev.pc.11.100160.000543. Quantum Theory of electronic structure of molecules. Annu. Rev. Phys. Chem.. 11. 1. 107–132. 1960. 1960ARPC...11..107L .
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.32.328. Expansion theorems for the total wave function and extended Hartree-Fock Schemes. 32. 2. 328–334. 1960. 1960RvMP...32..328L.
• Per-Olov. Löwdin. The Journal of Chemical Physics. Note on the separability theorem for electron pairs. 10.1063/1.1731935. 35. 1. 78. 1961. 1961JChPh..35...78L .
• Per-Olov. Löwdin. Journal of Mathematical Physics. 10.1063/1.1724312. Studies in perturbation theory. IV. Solution of eigenvalue problem by projection operator formalism. 3. 5. 969. 1962. 1962JMP.....3..969L .
• Per-Olov. Löwdin. Journal of Mathematical Physics. Studies in perturbation theory. V. Some aspects on the exact self-consistent field theory. 10.1063/1.1703860. 3. 6. 1171. 1962. 1962JMP.....3.1171L .
• Per-Olov. Löwdin. Journal of Applied Physics. 10.1063/1.1777106. Band theory, valence bond, and tight-binding calculations. 33. 1. 251. 1962. 1962JAP....33..251L .
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.34.80. Exchange, correlation, and spin effects in molecular and solid-state theory. 34. 1. 80–87. 1962. 1962RvMP...34...80L.
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.34.520. The normal constants of motion in quantum mechanics treated by projection technique. 34. 3. 520–530. 1962. 1962RvMP...34..520L.
• Jean-Louis. Calais. Per-Olov. Löwdin. Journal of Molecular Spectroscopy. 10.1016/0022-2852(62)90021-8. A simple method of treating atomic integrals containing functions of r₁₂. 8. 1–6. 203–211. 1962. 1962JMoSp...8..203C .
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.35.702. Wave and reaction operators in the quantum theory of many-article systems. 35. 3. 702–707. 1963. 1963RvMP...35..702L.
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.35.724. Proton tunneling in DNA and its biological implications. 35. 3. 724–732. 1963. 1963RvMP...35..724L.
• Per-Olov. Löwdin. Journal of Molecular Spectroscopy. 10.1016/0022-2852(63)90151-6. Studies in perturbation theor: Part I. An elementary iteration-variation procedure for solving the Schrödinger equation by partitioning technique. 10. 1–6. 12–33. 1963. 1963JMoSp..10...12L .
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.36.966. Angular momentum wavefunctions constructed by projector operators. 36. 4. 966–976. 1964. 1964RvMP...36..966L.
• Per-Olov. Löwdin. Journal of Molecular Spectroscopy. 10.1016/0022-2852(64)90106-7. Studies in perturbation theory: Part VI. Contraction of secular equations. 14. 1–4. 112–118. 1964. 1964JMoSp..14..112L .
• Per-Olov. Löwdin. Journal of Molecular Spectroscopy. 10.1016/0022-2852(64)90107-9. Studies in perturbation theory: Part VII. Localized perturbation. 14. 1–4. 199–130. 1964. 1964JMoSp..14..119L .
• Per-Olov. Löwdin. Journal of Molecular Spectroscopy. 10.1016/0022-2852(64)90108-0. Studies in perturbation theory: Part VIII. Separation of Dirac equation and study of the spin-orbit coupling and Fermi contact terms. 14. 1–4. 131–144. 1964. 1964JMoSp..14..131L .
• Per-Olov. Löwdin. Journal of Mathematical Physics. 10.1063/1.1704781. Studies in perturbation theory. IX. connection between various approaches in the recent development – evaluation of upper bounds to energy eigenvalues in Schrödinger's perturbation theory. 6. 8. 1341–1353. 1965. 1965JMP.....6.1341L . free.
• Per-Olov. Löwdin. Physical Review. 10.1103/PhysRev.139.A357. Studies in perturbation theory. X. Lower bounds to energy eigenvalues in perturbation-theory ground state. 139. 2A. A357–A372. 1965. 1965PhRv..139..357L .
• Per-Olov. Löwdin. The Journal of Chemical Physics. 10.1063/1.1701483. Studies in perturbation theory. XI. Lower bounds to energy eigenvalues, ground state, and excited states. 43. 10. S175–S185. 1965. 1965JChPh..43S.175L . 2060/19660007693. free.
• Book: Per-Olov. Löwdin. 10.1016/S0065-3276(08)60076-3. Quantum genetics and the aperiodic solid: Some aspects on the biological problems of heredity, mutations, aging and tumors in view of the quantum theory of the DNA molecule. 2. 213–360. 1966. 1966AdQC....2..213L. Advances in Quantum Chemistry. 978-0-12-034802-2. Quantum Genetics and the Aperiodic Solid.
• Per-Olov. Löwdin. Reviews of Modern Physics. 10.1103/RevModPhys.39.259. Group algebra, convolution algebra, and applications to quantum mechanics. 39. 2. 259–187. 1967. 1967RvMP...39..259L.
• Book: Per-Olov. Advances in Quantum Chemistry Volume 3. Löwdin. 10.1016/S0065-3276(08)60092-1. Quantum theory of time-dependent phenomena treated by the evolution operator technique. 3. 323–381. 1967. 1967AdQC....3..323L. 978-0-12-034803-9. 2060/19660007795.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560020612. Studies in perturbation theory XIII. Treatment of constants of motion in resolvent method, partitioning technique, and perturbation theory. 2. 6. 867–931. 1968. 1968IJQC....2..867L .
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560020715. Some comments on the treatment of symmetry properties in perturbation theory. 2. S2. 137–150. 1968. 1968IJQC....2..137L .
• Walter M.. MacIntyre. Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560020720. Electronic energy of the DNA replication plane. 2. S2. 207–217. 1968. 1968IJQC....2..207M .
• Manuel. Berrondo. Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560030604. The projection operator for a space spanned by a linearly dependent set. 3. 6. 767–780. 1969. 1969IJQC....3..767B .
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560030737. Some comments on the periodic system of elements. 3. S3A. 331–334. 1969. 1969IJQC....3..331L .
• Per-Olov. Löwdin. Annals of the New York Academy of Sciences. 10.1111/j.1749-6632.1969.tb56215.x. some aspects of the hydrogen bond in molecular biology. 158. 1. 86–95. 1969. 5256969. 1969NYASA.158...86L . 9646946.
• Book: Per-Olov. Advances in Quantum Chemistry Volume 5. Löwdin. 10.1016/S0065-3276(08)60339-1. On the nonorthogonality problem. 5. 185–199. 1970. 1970AdQC....5..185L. 978-0-12-034805-3.
• John. Gruninger. Yngve. Öhrn. Per-Olov. Löwdin. The Journal of Chemical Physics. Comments on the analysis of atomic correlation energies. 10.1063/1.1672824. 52. 11. 5551. 1970. 1970JChPh..52.5551G . free.
• Per-Olov. Löwdin. Osvaldo. Goscinski. International Journal of Quantum Chemistry. The exchange phenomenon, the symmetric group, and the spin degeneracy problem. 10.1002/qua.560040719. 4. S38. 533–591. 1970.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. Some properties of inner projections. 10.1002/qua.560050725. 5. S4. 231–237. 1971.
• Bernard. Laskowski. Per-Olov. Löwdin. Chemical Physics Letters. Treatment of constants of motion in the variation principle. Symmetry properties of variational wavefunctions. 10.1016/0009-2614(72)80441-X. 16. 1. 1–4. 1972. 1972CPL....16....1L .
• Per-Olov. Löwdin. P. K.. Mukherjee. Chemical Physics Letters. Some comments on the time-dependent variation principle. 10.1016/0009-2614(72)87127-6. 14. 1. 1–7. 1972. 1972CPL....14....1L .
• T.. Ahlenius. J.-L.. Calais. Per-Olov. Löwdin. Journal of Physics C: Solid State Physics. Some comments on the construction of an orthonornal set of LCAO basis functions for crystals. 10.1088/0022-3719/6/11/016. 6. 11. 1896. 1973. 1973JPhC....6.1896A .
• B.. Laskowski. P.. van Leuven. Per-Olov. Löwdin. Lowdin. Journal of Physics C: Solid State Physics. P -O. Electron gas test for the alternant molecular orbital method. 10.1088/0022-3719/6/18/007. 6. 18. 2777. 1973. 1973JPhC....6.2777L .
• Book: Per-Olov. Löwdin. 10.1016/S0065-3276(08)60318-4. Molecular structure calculations. 12. 263–316. 1980. 1980AdQC...12..263L. Advances in Quantum Chemistry. 978-0-12-034812-1.
• Per-Olov. Löwdin. Physica Scripta. 10.1088/0031-8949/21/3-4/002. Introductory remarks to Nobel Symposium on many-body theory of atomic systems. 21. 3–4. 229. 1980. 1980PhyS...21..229L . 250808961.
• Oscar E.. Taurian. Per-Olov. Löwdin. Acta Physica Academiae Scientiarum Hungaricae. 10.1007/BF03155558. Some remarks on the projector associated with the intersection of two linear manifolds. 51. 1–2. 5–12. 1981. 120887514.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560210105. Partitioning technique, perturbation theory, and rational approximations. 21. 1. 69–92. 1982.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560220847. On operators, superoperators, hamiltonians, and liouvillians. 22. S16. 485–560. 1982.
• Piotr. Froelich. Per-Olov. Löwdin. Journal of Mathematical Physics. 10.1063/1.525605. On the Hartree-Fock scheme for a pair of adjoint operators. 24. 1. 88. 1983. 1983JMP....24...88F .
• Per-Olov. Löwdin. Journal of Mathematical Physics. 10.1063/1.525604. On the stability problem of a pair of adjoint operators. 25. 1. 70–87. 1983. 1983JMP....24...70L .
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560240615. On the Sanibel coefficients in the expansion of spin-projected Slater determinants. 24. 1. 729–745. 1983 .
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560260705. Some aspects on the relation between the natural sciences and the human mind: An introduction to a panel discussion on the origin of life and mind. 26. S11. 31–43. 1984.
• Per-Olov. Löwdin. Physica Scripta. 10.1088/0031-8949/32/4/002. On the connection between the resolvent methods and partitioning technique, rational approximation, and perturbation theory. 32. 4. 261. 1985. 1985PhyS...32..261L . 250768623.
• Book: Per-Olov. Advances in Quantum Chemistry Volume 17. Löwdin. 10.1016/S0065-3276(08)60305-6. Some aspects on the Hamiltonian and Liouvillian formalism, the special propagator methods, and the equation of motion approach. 17. 285–334. 1985. 1985AdQC...17..285L. 978-0-12-034817-6.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560300763. Some comments on the method of complex scaling to find physical resonance states. 30. S20. 743–748. 1986.
• Young Shik. Shik Kong. Mu Shik. Jhon. Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560320820. Studies on proton transfers in water clusters and DNA base pairs. 32. S14. 189–209. 1987.
• Book: Per-Olov. Löwdin. On linear algebra, the least squares method and the search for linear relations by regression analysis in quantum chemistry and other sciences. 23. 83. 1992. 1992AdQC...23...83L . 10.1016/S0065-3276(08)60029-5. Advances in Quantum Chemistry. 978-0-12-034823-7 .
• Book: Per-Olov. Löwdin. István. Mayer. 10.1016/S0065-3276(08)60101-X. Some studies of the general Hartree-Fock method. 24. 79–114. 1992. 1992AdQC...24...79L. Advances in Quantum Chemistry. 978-0-12-034824-4.
• Per-Olov. Löwdin. Foundations of Physics. 10.1007/BF01883380. Some aspects of objectivity and reality in modern science. 22. 1. 41–105. 1992. 1992FoPh...22...41L . 121458194.
• István. Mayer. Per-Olov. Löwdin. Chemical Physics Letters. 10.1016/0009-2614(93)85341-K. Some comments of the general Hartree-Fock method. 202. 1–2. 1–6. 1993. 1993CPL...202....1M .
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560480403. Some remarks on the resemblance theorems associated with various orthonormalization procedures. 48. 4. 225–232. 1993.
• Rodney J.. Bartlett. Erik. Deumens. Per-Olov. Löwdin. David A.. Micha. Hendrik J.. Monkhorst. John R.. Sabin. Samuel B.. Trickey. Michael C.. Zerner. International Journal of Quantum Chemistry. 10.1002/qua.560520803. On the occasion of Yngve Öhrn's 60th birthday. 52. S28. 3–5. 1994.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/qua.560570102. In memory of Jean-Louis Calais. 57. 1. 1–2. 1996.
• Per-Olov. Löwdin. International Journal of Quantum Chemistry. 10.1002/(SICI)1097-461X(1997)64:2<157::AID-QUA2>3.0.CO;2-V. Some aspects on the development of the natural sciences and their importance for modern society and for our global environment. 64. 2. 158–169. 1997.
• Book: Per-Olov. Löwdin. Some comments on the foundations of physics. Some Comments on the Foundations of Physics. Edited by Lowdin P O. Published by World Scientific Publishing Co. Pte. Ltd. 978-981-02-2913-9. World Scientific. 1998. 1998scfp.book.....L. 10.1142/3331.
• Book: Per-Olov. Advances in Quantum Chemistry Volume 30. Löwdin. 10.1016/S0065-3276(08)60520-1. Some aspects on the Bloch-Lindgren equation and a comparison with the partitioning technique. 30. 415–432. 1998. 1998AdQC...30..415L. 978-0-12-034830-5.
• Per-Olov. Löwdin. Advances in Physics. 10.1080/00018730110102196. Quantum theory of cohesive properties of solids. 50. 6. 597–756. 2001. 2001AdPhy..50..597L . 123635495.

External links

• Jan . Linderberg . Biographical Memoir . Proc. Am. Philos. Soc. . 147 . 2 . 175–180 . 2003 . 2016-02-12 . https://web.archive.org/web/20160411042337/https://amphilsoc.org/sites/default/files/proceedings/210.pdf . 2016-04-11 . dead.
• 10.1002/qua.10096. Per-Olov Löwdin Curriculum Vitae. International Journal of Quantum Chemistry. 90. 1. 1–11. 2002. free.
• Kimio Ohno Early Ideas in the history of Quantum Chemistry (1976)

• The Löwdin Lectures, Uppsala University
• Quantum Theory Project founded by Löwdin at the University of Florida in 1960

Notes and References

1. Per-Olov. Löwdin. The Journal of Chemical Physics. On the non-orthogonality problem connected with the use of atomic wave functions in the theory of molecules and crystals. 10.1063/1.1747632. 1950. 18. 365. 1950JChPh..18..365L. 3 .
2. [John C. Slater|J. C. Slater]
3. Per-Olov. Löwdin. Advances in Physics. 10.1080/00018735600101155. Quantum theory of cohesive properties of solids. 5. 17. 1. 1956. 1956AdPhy...5....1L .
4. Reed, Alan E., Larry A. Curtiss, and Frank Weinhold. "Intermolecular interactions from a natural bond orbital, donor-acceptor viewpoint." Chemical Reviews 88.6 (1988): 899-926.
5. 10.1002/jcc.22885 . Multiwfn: A multifunctional wavefunction analyzer . 2012 . Lu . Tian . Chen . Feiwu . Journal of Computational Chemistry . 33 . 5 . 580–592 . 22162017 . 13508697 .
6. Web site: APS Member History . 2022-05-31 . search.amphilsoc.org.